Cement Calculator
Calculate the number of cement bags needed for a given volume of concrete and mix ratio.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Enter your concrete volume and mix ratio to find the number of 50kg cement bags needed.
Your result
8.5
Cement bags (50kg)
Cement weight423.6
Dry material volume1.617
AI explanation
Formula
Dry volume = wet volume × (1 + wastage%) × 1.54; cement volume = dry volume × (cement parts ÷ total parts); bags = cement volume ÷ 0.0347 m³Worked example
1 m³ of M20 concrete, 5% wastage
| Field | Value |
|---|---|
| Wet concrete volume (m³) | 1 |
| Concrete mix | M20 (1:1.5:3) |
| Wastage allowance (%) | 5 |
| Cement bags (50kg) | 8.5 |
| Cement weight | 423.6 |
| Dry material volume | 1.617 |
Assumptions
- One cement bag is 50kg (~0.0347 m³, based on cement's loose bulk density of ~1440 kg/m³).
- Dry volume = wet volume × 1.54, the standard site-estimation factor for voids that close up during mixing.
Frequently asked questions
How much does one cement bag weigh?
50kg is the standard cement bag size in India.
How many bags of cement are needed per cubic meter of M20 concrete?
About 8-8.5 bags per cubic meter of wet concrete for a 1:1.5:3 (M20) mix, including a typical wastage allowance.
Where do I find the "wet concrete volume" to enter here?
Use the Concrete Volume, Slab, Footing, or Column Calculator to compute your volume first, then enter it here — or use those calculators directly, since they include this same cement/sand/aggregate breakdown.